Elastomers – Biochemical Engineer MCQs

1. Which of the following is the tensile strength (kg/cm²) of vulcanised rubber?

(A) 200

(B) 2000

(C) 500

(D) 5000

2. Which of the following is the percentage of butadiene and styrene in Buna-S?

(A) 60% and 40% respectively

(B) 75% and 25% respectively

(C) 80% and 20% respectively

(D) 50% each

3. The application of SBR is ____________.

(A) Conveyor belts for food

(B) Lining of tanks

(C) Oil-resistance foam

(D) Printing rollers

4. __________ act as a catalyst in preparation of Buna-S.

(A) Cumene hydroperoxide

(B) Hydrogen peroxide

(C) Benzoyl peroxide

(D) Acrylonitrile

5. ___________ has the best resistance to oils.

(A) Natural rubber

(B) Neoprene

(C) Nitrile rubber

(D) Styrene rubber

6. ____________ act as a catalyst in the preparation of butyl rubber.

(A) Lewis base

(B) Cumene hydroperoxide

(C) Anhydrous AlCl₃

(D) Grignard reagent

7. The statement that is incorrect about the SBR is __________.

(A) This has high abrasion resistance

(B) This has low load-bearing capacity

(C) This swells in oils and solvents

(D) This has low oxidation resistance

8. Which of the following is the solvent that is used in the preparation of butyl rubber?

(A) Methyl iodide

(B) Methyl halide

(C) Methyl sulphide

(D) Methyl chloride

9. Which of the following is the major constituent of butyl rubber?

(A) Chloroprene

(B) Isoprene

(C) Isobutylene

(D) Acrylonitrile

10. Which of the following is the Natural rubber?

(A) Acrylonitrile

(B) Ethylene glycol

(C) Butadiene

(D) Polyisoprene

11. Not the essential structural requirement of an elastomer is ______________.

(A) Occasional cross-linking

(B) Weak intermolecular forces

(C) Long flexible chains

(D) Rigidity in structure

12. Not an application of neoprene is ____________.

(A) Conveyor belts

(B) Wire and cable insulation

(C) Printing rollers

(D) Adhesives

13. In the vulcanisation process, with which of the following the raw rubber is heated?

(A) Oxygen

(B) Calcium

(C) Carbon

(D) Sulphur

14. Which of the following is the structural formula of isoprene?

(A) 2-methyl-1,3-butadiene

(B) 3-benzyl-1,2-butadiene

(C) 2-benzyl-1,3-butadiene

(D) 3-methyl-1,2-butadiene

15. At which of the following temperatures is the raw rubber heated for the vulcanisation process?

(A) 0–10°C

(B) 10–50°C

(C) 50–100°C

(D) 100–140°C

16. Which of the following is the incorrect statement?

(A) Raw rubber is durable

(B) Raw rubber is attacked by oxidizing agent

(C) In the organic solvents, it always undergoes the swelling and disintegration

(D) The Raw rubber is always weak and has very low tensile strength

17. The incorrect statement is that the Vulcanised rubber has ______________.

(A) Excellent resilience

(B) Only slight tackiness

(C) High elasticity

(D) Tensile strength 10 times more than raw rubber